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Skeptics Query New Electricity-Saving Plug

Claims made by the manufacturer of the GreenPlug have produced a storm of controversy as Consumer Reports cries foul

STORE shelves are filling up with so-called ``green'' products promising to benefit the environment. A recent controversy pitting the influential magazine Consumer Reports against a popular new energy-saving device shows that it can be as difficult for buyers to confirm such claims as for manufacturers to defend them.

The controversy concerns the GreenPlug Electricity Saver ($29-$39 retail). Consumers snapped up 500,000 in 1993, the plug's first year on the market. Gross revenue was $10 million for the fledgling manufacturer, Green Technologies Inc., of Boulder, Colo.

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The GreenPlug is supposed to prevent energy waste by appliances whose constant-speed motors operate at less than full load - as is especially true of older refrigerators. Research conducted for the space shuttle showed that such motors can be made to do the same work with less heat, noise, and power consumption just by lowering the voltage of the power supply.

John and Wyck Hay, two of the founders of the Celestial Seasonings Herb Tea Company, started Green Technologies in 1990 to apply that finding to home appliances. In the United States alone, there are more than 140 million refrigerators in use, accounting for an average of 16 percent of the household electric bill. That share can run as high as 25 percent in a small apartment.

Two years of research resulted in the GreenPlug. Connecting between wall socket and refrigerator, the device contains an analog computer that gives a motor full power (120 volts on average) for start-up, then reduces the power to 106 volts.

That boosts the efficiency, but a host of factors affect how much electricity and money are saved. Line voltage varies from home to home.

Older refrigerators are the most overpowered and, thus, save the most energy with a GreenPlug. Refrigerators less than two years old are so efficient already that a GreenPlug actually makes them waste electricity.

The higher the voltage, the larger the difference a GreenPlug makes.

Higher power costs shorten the payback time. The population-weighted national average is 10 cents per kilowatt-hour (kWh). But some residents in Washington State pay 1.5 cents. Some in Alaska pay 41.6 cents.

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Then come highly individual household factors like the number of children of refrigerator-opening age. All in all, the GreenPlug should save the average consumer $20 a year, says Steve Ehli, director of public relations for Green Technologies.

Smart Energy Services Inc., a for-profit subsidiary of Central Vermont Public Service in Rutland, Vt., liked the product so much that last fall it paid $1.2 million for a 5 percent stake in Green Technologies. Smart Energy Services will also handle direct sales to 3,500 utilities in North America for demand-side management programs.

Unfavorable review

Controversy over the GreenPlug began when Bernard Deitrick, a project leader at Consumers Union, tested the device on refrigerators made in 1969, 1975, 1978, and 1992. His results appeared in an unfavorable review in the November issue of Consumer Reports, drawing a barrage of challenges from Green Technologies as well as GreenPlug vendors and customers.

Although the GreenPlug lowered the voltage as it was designed to do, Consumer Reports questioned how quickly - if ever - electricity savings attributable to the plug would repay its cost. People would be better off buying a new, high-efficiency refrigerator, the magazine advised.

But not everyone can afford one, counters Mark Eisen, manager of environmental marketing at Home Depot Inc. in Atlanta. The GreenPlug gives buyers an affordable alternative. ``That's what responsible environmental marketing is about,'' he says.

Consumer Reports also said that the GreenPlug didn't give a claimed 25 percent saving worth $50 a year. The savings on the oldest model was the best at 8.6 percent, worth $20 a year.

Green Technologies responded that by November it had discontinued a pamphlet that implied that the GreenPlug could deliver a 25-percent savings. And it had never used the $50 figure.

Ned Groth, director of technical policy and public service at Consumers Union, admits that the $50 figure came from the magazine's own calculation. But it was based on the 25 percent savings cited in Green Technologies literature when the review was done, he says.

The manufacturer also said Consumers Union mistested the product by not following instructions. Those instructions say that the lower voltage caused by the GreenPlug will slow the fan that blows air from the freezer compartment to the refrigerator, making the freezer colder. To maintain the temperature, the user is directed to move the freezer control to a warmer setting.

However, by one calculation, a 5 degree F upward adjustment in freezer-compartment temperature reduces electricity consumption by an average 15 percent - with or without a GreenPlug. So Consumers Union chose not to make the adjustment in order to test the impact of the GreenPlug alone.

In its tests, six temperature sensors in packages of spinach found no change in freezer coldness greater than 1.4 degrees. That, Mr. Deitrick says, was not enough to warrant changing the setting.

Eric David, a professor of electrical technology at Long Beach Community College in California, stuck up for the GreenPlug in letters to Consumer Reports. He measured a savings of 18 percent for his 1984 model refrigerator, and the temperature in his freezer did not change even after adjusting it as recommended. For his situation, he calculated a payback period of less than nine months.

``There are definitely savings,'' Professor David says.

`Extravagant' claims

Documents subsequently provided by the manufacturer only bolstered Deitrick's opinion. ETL Testing Laboratories Inc. of Cortland, N.Y., working for Green Technologies and following its instructions, found that the freezer compartments on GreenPlug-equipped refrigerators warmed 7 degrees to 9 degrees while electrical consumption fell just 15 percent.

``They give the device credit for the energy saved by adjusting the freezer's temperature,'' says Ned Groth, director of technical policy and public service at Consumers Union. He calls the company's claims ``extravagant'' and ``misleading.'' Adds Deitrick: ``It works a little.''

E Source Inc. of Boulder, Colo., also reviewed the product for the manufacturer. In tests that E Source monitored at Green Technologies, freezer temperatures rose 5 degrees to 9 degrees in three refrigerators and went unchanged in a fourth. Savings ranged from 8 percent to 15 percent. When E Source asked the company to keep freezer temperatures constant, though, the savings fell to 4 percent.

Bradley Davids, vice president of member services at E Source, says the GreenPlug is ``a legitimate energy-saving device.'' But he disagrees with the advertising. ``I don't believe the savings are in proportion to the hype.''

``Everybody's findings are basically the same. [The GreenPlug] has promise. But is there a break-even?'' asks William Smart, business manager of Scientific Certification Systems of Oakland, Calif. SCS certifies the validity of claims by ``green'' products for manufacturers and has been retained by Green Technologies.

That effort, led by Mr. Smart, has just begun. But he suspects that the annual savings possible with a GreenPlug ranges from minus $2 to $30. At least 20 percent of homeowners, and maybe as much as 66 percent, could save $20 a year with the GreenPlug.

Few customer complaints

Green Technologies ordered tests of the GreenPlug on up to 2,800 refrigerators through next year. Mr. Ehli says the company will not put that data in stores. Instead, potential buyers will call an 800 number to learn how their model of refrigerator performed.

Meanwhile, there is little evidence of consumer dissatisfaction. Sales topped 45,000 units last month. The return rate is less than 0.2 percent, Ehli says. In April, the General Services Administration approved the GreenPlug for direct purchase by federal agencies.

Northeast Utilities Services Company in Hartford, Conn., gave GreenPlugs to 1,500 low-income customers last year and has continued to hand them out at a rate of 200 a month, spokesman Bruno Ranniello says. ``The response has been very, very favorable,'' he says.

Eisen says the product remains in his 275 stores. ``Sales are great,'' he says.

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